誰告訴你環境變數可以用來傳輸設定檔了…
可以用環境變數的意思是，有些軟體既能辨識環境變數中提供的配置，又能辨識檔案形式的配置，不過，很不幸，Nginx不在此列。

以wget為例，設定HTTP代理程式時，可以選用以下任一方式：

• 在設定檔中加一行http_proxy = http://example.com/xxx

• 將系統環境變數$http_proxy设定为http://example.com/xxx

兩種方法的作用是相同的。

當然，你可以在Docker容器裡寫一個Shell腳本，根據環境變數來修改設定檔的內容，但這就是另一個主題了。 Github上有不少實現類似功能的工具，如Tiller。

補充一個資料：How Should I Get Application Configuration into my Docker Containers?

哦，在啟動容器的時候要帶參數，例如：
./docker run --detach --name wordpress --net wordnet --publish 80:80 --env WORDPRESS_DB_HOST=mysql --env WORDPRESS_DB_PASSWORD=xxxPRESS_DB_HOST=mysql --env WORDPRESS_DB_PASSWORD=xxx xxxxxx 4.4

當然在容器啟動指令裡要處理帶進來的參數：

cat /entrypoint.sh

#!/bin/bash set -e if [[ "" == apache2* ]] || [ "" == php-fpm ]; then if [ -n "$MYSQL_PORT_3306_TCP" ]; then if [ -z "$WORDPRESS_DB_HOST" ]; then WORDPRESS_DB_HOST='mysql' else echo >&2 'warning: both WORDPRESS_DB_HOST and MYSQL_PORT_3306_TCP found' echo >&2 " Connecting to WORDPRESS_DB_HOST ($WORDPRESS_DB_HOST)" echo >&2 ' instead of the linked mysql container' fi fi if [ -z "$WORDPRESS_DB_HOST" ]; then echo >&2 'error: missing WORDPRESS_DB_HOST and MYSQL_PORT_3306_TCP environment variables' echo >&2 ' Did you forget to --link some_mysql_container:mysql or set an external db' echo >&2 ' with -e WORDPRESS_DB_HOST=hostname:port?' exit 1 fi # if we're linked to MySQL and thus have credentials already, let's use them : ${WORDPRESS_DB_USER:=${MYSQL_ENV_MYSQL_USER:-root}} if [ "$WORDPRESS_DB_USER" = 'root' ]; then : ${WORDPRESS_DB_PASSWORD:=$MYSQL_ENV_MYSQL_ROOT_PASSWORD} fi : ${WORDPRESS_DB_PASSWORD:=$MYSQL_ENV_MYSQL_PASSWORD} : ${WORDPRESS_DB_NAME:=${MYSQL_ENV_MYSQL_DATABASE:-wordpress}} if [ -z "$WORDPRESS_DB_PASSWORD" ]; then echo >&2 'error: missing required WORDPRESS_DB_PASSWORD environment variable' echo >&2 ' Did you forget to -e WORDPRESS_DB_PASSWORD=... ?' echo >&2 echo >&2 ' (Also of interest might be WORDPRESS_DB_USER and WORDPRESS_DB_NAME.)' exit 1 fi if ! [ -e index.php -a -e wp-includes/version.php ]; then echo >&2 "WordPress not found in $(pwd) - copying now..." if [ "$(ls -A)" ]; then echo >&2 "WARNING: $(pwd) is not empty - press Ctrl+C now if this is an error!" ( set -x; ls -A; sleep 10 ) fi tar cf - --one-file-system -C /usr/src/wordpress . | tar xf - echo >&2 "Complete! WordPress has been successfully copied to $(pwd)" if [ ! -e .htaccess ]; then # NOTE: The "Indexes" option is disabled in the php:apache base image cat > .htaccess <<-'EOF' # BEGIN WordPress  RewriteEngine On RewriteBase / RewriteRule ^index\.php$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.php [L]  # END WordPress EOF chown www-data:www-data .htaccess fi fi # TODO handle WordPress upgrades magically in the same way, but only if wp-includes/version.php's $wp_version is less than /usr/src/wordpress/wp-includes/version.php's $wp_version # version 4.4.1 decided to switch to windows line endings, that breaks our seds and awks # https://github.com/docker-library/wordpress/issues/116 # https://github.com/WordPress/WordPress/commit/1acedc542fba2482bab88ec70d4bea4b997a92e4 sed -ri 's/\r\n|\r/\n/g' wp-config* if [ ! -e wp-config.php ]; then awk '/^\/\*.*stop editing.*\*\/$/ && c == 0 { c = 1; system("cat") } { print }' wp-config-sample.php > wp-config.php <<'EOPHP' // If we're behind a proxy server and using HTTPS, we need to alert Wordpress of that fact // see also http://codex.wordpress.org/Administration_Over_SSL#Using_a_Reverse_Proxy if (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https') { $_SERVER['HTTPS'] = 'on'; } EOPHP chown www-data:www-data wp-config.php fi # see http://stackoverflow.com/a/2705678/433558 sed_escape_lhs() { echo "$@" | sed 's/[]\/$*.^|[]/\&/g' } sed_escape_rhs() { echo "$@" | sed 's/[\/&]/\&/g' } php_escape() { php -r 'var_export(('') $argv[1]);' "" } set_config() { key="" value="" var_type="${3:-string}" start="(['\"])$(sed_escape_lhs "$key")\s*," end="\);" if [ "${key:0:1}" = '$' ]; then start="^(\s*)$(sed_escape_lhs "$key")\s*=" end=";" fi sed -ri "s/($start\s*).*($end)$/$(sed_escape_rhs "$(php_escape "$value" "$var_type")")/" wp-config.php } set_config 'DB_HOST' "$WORDPRESS_DB_HOST" set_config 'DB_USER' "$WORDPRESS_DB_USER" set_config 'DB_PASSWORD' "$WORDPRESS_DB_PASSWORD" set_config 'DB_NAME' "$WORDPRESS_DB_NAME" # allow any of these "Authentication Unique Keys and Salts." to be specified via # environment variables with a "WORDPRESS_" prefix (ie, "WORDPRESS_AUTH_KEY") UNIQUES=( AUTH_KEY SECURE_AUTH_KEY LOGGED_IN_KEY NONCE_KEY AUTH_SALT SECURE_AUTH_SALT LOGGED_IN_SALT NONCE_SALT ) for unique in "${UNIQUES[@]}"; do eval unique_value=$WORDPRESS_$unique if [ "$unique_value" ]; then set_config "$unique" "$unique_value" else # if not specified, let's generate a random value current_set="$(sed -rn "s/define\((([\'\"])$unique\s*,\s*)(['\"])(.*)\);//p" wp-config.php)" if [ "$current_set" = 'put your unique phrase here' ]; then set_config "$unique" "$(head -c1M /dev/urandom | sha1sum | cut -d' ' -f1)" fi fi done if [ "$WORDPRESS_TABLE_PREFIX" ]; then set_config '$table_prefix' "$WORDPRESS_TABLE_PREFIX" fi if [ "$WORDPRESS_DEBUG" ]; then set_config 'WP_DEBUG' 1 boolean fi TERM=dumb php -- "$WORDPRESS_DB_HOST" "$WORDPRESS_DB_USER" "$WORDPRESS_DB_PASSWORD" "$WORDPRESS_DB_NAME" <<'EOPHP' connect_error) { fwrite($stderr, "\n" . 'MySQL Connection Error: (' . $mysql->connect_errno . ') ' . $mysql->connect_error . "\n"); --$maxTries; if ($maxTries <= 0) { exit(1); } sleep(3); } } while ($mysql->connect_error); if (!$mysql->query('CREATE DATABASE IF NOT EXISTS `' . $mysql->real_escape_string($argv[4]) . '`')) { fwrite($stderr, "\n" . 'MySQL "CREATE DATABASE" Error: ' . $mysql->error . "\n"); $mysql->close(); exit(1); } $mysql->close(); EOPHP fi exec "$@"